Friction profile for the top of pool grate bars

ABSTRACT

An inventive top profile design of friction ridges on top of grate bars in a swimming pool. The profiles exhibit a multiple of right angled friction ridges which are stacked within each other in a direction which is perpendicular to the longitudinal direction of the grate bars. The right angled ridges resemble the well known chevron format. The right angled friction ridges increase the coefficient of friction to above 1.0 ASTM. The design of the friction ridges drains off water quickly and reduces the travel time of water the grate bars. The design also prevents stagnant water forming any mold formation. The tops of the friction ridges are rounded so that no sharp edges are present to enhance the comfort under the bare feet.

BACKGROUND OF THE INVENTION

Swimming pools have various ways of cleaning the debris which is floating on the surface of the water. One way is to let the water drain into a filter box having a floating weir therein. Another way is to let the water overflow or slosh onto a grate bar system which covers a sump running around the perimeter of the pool. The grate bar system is being installed over the top of the sump. The grate bar system is even with the concrete walk which extends around the pool as a walkway.

BRIEF DESCRIPTION OF THE INVENTION

The water sloshing over the grate bar system constantly keeps the surface of the grate bar system wet. It also of the utmost importance that the surface of the grate bars are as slippery-proof as possible. There are grate bars having a friction surface made up of ribs that run parallel to the longitudinal extent of the pool and there grate bars that have a friction surface made up of ribs running perpendicular to the longitudinal extent of the pool. The perpendicular ribs have proofed to be most useful because the water in between the ribs tends to empty quicker than the ribs running perpendicular to the pool. However, it has been found that the inventive rib profile is most beneficial in emptying the water between the ribs. The inventive profile consists of angular ribs that are stacked within each other in a certain direction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of the friction surface profiles of grate bars;

FIG. 2 is a top view of a grate bar including angles;

FIG. 3 is a cross section through a grate bar.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a top view of at least three grate bars 1, 2, and 3 which are installed over a sump or drainage channel located within the pool deck. The grate bars 1-3 are supported at a level surface of the pool deck by grate bar support bars 4-7 which are installed perpendicular to the drainage channel. The tops of the grate bars represent a certain friction profile which exhibit an increased coefficient of friction to above 1.0 ASTM. The friction profiles are so arranged so that they present right angular friction bars 9-14 which are stacked within each other across the grate bar. This profile may generally be known as a chevron.

Experiments have found that this design is effective in draining water quickly while it reduces the travel time of the water over the grates, thereby preventing mold from forming because of stagnant water. There are no sharp edges which creates comfort under bare feet. The friction design helps to keep the grate bars cleaner because stains are prevented.

FIG. 2 illustrates a single piece of a grate bar where the angle B represents an angle of 45 degrees, angle B, between the direction of any of the ribs and an edge of the grate bars. Each of the chevron profiles exhibit an angle of 90 degrees. The break line A-A is shown as a cross section in FIG. 3 where it can be seen that the tops of the friction ridges are rounded at 15 which prevents any discomfort for bare feet.

It can now be seen that the inventive friction profile has many advantages over the straight ridges known in the prior art. 

1. A top profile design for grate bars in a swimming pool, said grate bars are supported by perpendicular support bars, said design exhibiting right angled friction ridges which are stacked relative to each other in a direction which is perpendicular to a longitudinal direction of the grate bars to thereby represent the form of a chevron.
 2. The profile design of claim 1, wherein straight edges of all of said right angled friction ridges form an angle of 45 degrees relative to longitudinal edges of the grate bars.
 3. The profile design of claim 1, wherein the coefficient of friction of the profile on top of said grate bars is above 1.0 ASTM.
 4. The profile design of claim 1, wherein each top of said friction ridges is rounded. 